Advanced Search not using proper operator with multipule groups

On the demo site I created a test group with 2 contacts in the group. One of the contacts was also in a group on the demo site called Government entity sg

I went to the advanced search and did a search with those 2 groups listed. The search operator was and. The expected result i would have thought is it returns any contacts that are in both groups i.e. 1. However returned a search where the operator would have been or i.e. it looked for contacts that were in either group

Seamus